package com.cjm.algorithm.dp;

public class Ti70 {
    public static void main(String[] args) {
        Ti70 ti70 = new Ti70();
        ti70.climbStairs(20);
        System.err.println("ob");
    }
    public int climbStairs(int n) {
        if (n <= 2) {
            return n;
        }
        int[] dp = new int[n+1];
        dp[1] = 1;
        dp[2]  =2;
        for (int i = 3; i <= n; i++) {
            dp[i] = dp[i - 1] + dp[i - 2];
        }
        return dp[n];
    }
}
